I wonder if anyone can shed some light on this please, as I am not sure 
where to go next with it.
Essentially I attempted to beat the rush to Gutsy by upgrading from 
Feisty this morning. In retrospect I should have first uninstalled the 
nvidia drivers that were installed by Envy on my feisty build, but I am 
afraid that thought only came to me with the benefit of hindsight!
Anyway, I suspect the presence of the nvidia drivers upset dpkg and 
caused that component of the upgrade to fall over, necessitating a 
reversion to vesa drivers.
I have tried to uninstall (purge, in fact) everything that might be 
causing the following error, but no matter what I do it seems to be 
present in one form or another when I try to install either nvidia-glx 
or nvidia-glx-new.
The error is:
Unpacking nvidia-glx (from 
.../nvidia-glx_1%3a1.0.9639+2.6.22.4-14.9_i386.deb) ...
dpkg-divert: `diversion of /usr/lib/libGL.so.1 to 
/usr/lib/nvidia/libGL.so.1.xlibmesa by nvidia-glx' clashes with 
`diversion of /usr/lib/libGL.so.1 to /usr/lib/nvidia/libGL.so.1.xlibmesa 
by nvidia-glx-new'
dpkg: error processing 
/var/cache/apt/archives/nvidia-glx_1%3a1.0.9639+2.6.22.4-14.9_i386.deb 
(--unpack):
 subprocess pre-installation script returned error exit status 2
Errors were encountered while processing:
 /var/cache/apt/archives/nvidia-glx_1%3a1.0.9639+2.6.22.4-14.9_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
[full text appended below]
Google threw up a few (dated) suggestions, but I have exhausted those 
and am stuck now.
Any thoughts on where to go next?
Sean
[full text]
root@BENDER:~# apt-get install nvidia-glx
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following extra packages will be installed:
  linux-restricted-modules-2.6.22-14-386 nvidia-kernel-common
Suggested packages:
  avm-fritz-firmware-2.6.22-14 nvidia-kernel-source
The following NEW packages will be installed
  linux-restricted-modules-2.6.22-14-386 nvidia-glx nvidia-kernel-common
0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded.
Need to get 4493kB/21.2MB of archives.
After unpacking 57.5MB of additional disk space will be used.
Do you want to continue [Y/n]?
Get: 1 http://gb.archive.ubuntu.com gutsy/restricted nvidia-glx 
1:1.0.9639+2.6.22.4-14.9 [4493kB]
Fetched 4493kB in 7s 
(635kB/s)                                                                                                                             
 
Selecting previously deselected package nvidia-kernel-common.
(Reading database ... 170162 files and directories currently installed.)
Unpacking nvidia-kernel-common (from 
.../nvidia-kernel-common_20051028+1ubuntu7_all.deb) ...
Selecting previously deselected package 
linux-restricted-modules-2.6.22-14-386.
Unpacking linux-restricted-modules-2.6.22-14-386 (from 
.../linux-restricted-modules-2.6.22-14-386_2.6.22.4-14.9_i386.deb) ...
Unpacking nvidia-glx (from 
.../nvidia-glx_1%3a1.0.9639+2.6.22.4-14.9_i386.deb) ...
dpkg-divert: `diversion of /usr/lib/libGL.so.1 to 
/usr/lib/nvidia/libGL.so.1.xlibmesa by nvidia-glx' clashes with 
`diversion of /usr/lib/libGL.so.1 to /usr/lib/nvidia/libGL.so.1.xlibmesa 
by nvidia-glx-new'
dpkg: error processing 
/var/cache/apt/archives/nvidia-glx_1%3a1.0.9639+2.6.22.4-14.9_i386.deb 
(--unpack):
 subprocess pre-installation script returned error exit status 2
Errors were encountered while processing:
 /var/cache/apt/archives/nvidia-glx_1%3a1.0.9639+2.6.22.4-14.9_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)